Road-surfacing vehicles are known which comprise a chamber for the material, an outlet and means for mixing the material as it passes to a surface distributor, in the form of a laying box, all of which are an integral part of the vehicle. The laying box will usually be provided at the rear of the vehicle. The road surfacing materials pass out from the laying box onto the road being surfaced.
These vehicles can be used very satisfactorily to surface open areas. However, in view of the limited maneuverability of the vehicles, the application of microasphalt or other road-surfacing materials to curved and confined areas such as lay-bys, bellmouths, hammer heads and road islands, has traditionally been carried out by hand.
By contrast, U.S. Pat. No. 4,215,949 and U.S. Pat. No. 4,676,689 disclose two types of apparatus which are not adapted for surfacing open areas, but which are specifically constructed for patching pavements, i.e. for filling potholes in the surface of an asphalt pavement or roadway. Thus, for example, U.S. Pat. No. 4,215,949 shows a vehicle having a supply hopper mounted along one side which serves to hold a quantity of asphalt. The supply hopper can be lowered to ground level to allow a truck to empty asphalt or other patching material into it through its open top and then raised for transport and use. The vehicle also has a distribution hopper mounted at the end of a remotely controlled arm extending from the front of the vehicle. The arm has a pair of articulated joints which allow the hopper to be positioned over a range of positions by the vehicle operator. The distribution hopper, which has an open top, is filled by placing it under the forward end of the supply hopper. The supply hopper has an auger in it which drives the asphalt forward to be discharged through a downwardly facing opening and into the underlying distribution hopper. The asphalt in he supply hopper is kept warm by the use of a flame inside the auger tube. Once filled, the operator of the vehicle moves the distribution hopper over an area to be repaired and remotely operates a door at the bottom of the distribution hopper, allowing a desired amount of asphalt to be deposited on the roadway. A remotely controlled tamper, mounted on the distribution hopper, then tamps the asphalt in place.
it can readily be appreciated that although the vehicle described in U.S. Pat. No. 4,215,949 would be suited to operating in curved and confined areas, it is only suitable for small scale work (of filling in potholes) and would not be at all suitable for surfacing open areas.
EP-A-0467255 discloses a surface Laying vehicle provided with a distribution head which includes a laying box, the distribution head being slidably mounted for movement in a vertical direction.
GB-A-2216094 discloses a transporting and dispensing truck, provided with a trough which is pivotally mounted about both a horizontal axis and a vertical axis.